Nonlocality effects on color spin locking condensates

Aguilera, Deborah N.; Blaschke, D.; Grigorian, H.; Scoccola, N. N.

doi:10.1103/physrevd.74.114005

Cited by 35 publications

(43 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1.0 MeV. Most prominent in this context is the color-spinlocking (CSL) phase [89,90] which has been evaluated in detail in the isotropic case for the local [91] and nonlocal NJL model [92]. The neutrino emissivity and bulk viscosity of such a phase have been discussed in Ref.…”

Section: Hybrid Starsmentioning

confidence: 99%

Influence of the stiffness of the equation of state and in-medium effects on the cooling of compact stars

2016

Self Cite

View full text Add to dashboard Cite

Abstract. Measurements of the low masses for the pulsar PSR J0737-3039B, for the companion of PSR J1756-2251 and for the companion of PSR J0453+1559 on the one hand and of the high masses for the pulsars PSR J1614-2230 and PSR J0348-0432 on the other demonstrate the existence of compact stars with masses in a broad range from 1.2 to 2 M . The most massive of these objects might be hybrid stars. To fulfill the constraint Mmax > 2 M with a reserve we exploit the stiff DD2 hadronic equation of state (EoS) without and with excluded volume (DD2vex) correction, which produce maximum neutron star masses of Mmax = 2.43 M and 2.70 M , respectively. We show that the stiffness of the EoS does not preclude an explanation of the whole set of cooling data within "nuclear medium cooling" scenario for compact stars by a variation of the star masses. We select appropriate proton gap profiles from those exploited in the literature and allow for a variation of the effective pion gap controlling the efficiency of the medium modified Urca process. However, we suppress the possibility of pion condensation. In general, the stiffer the EoS the steeper a decrease with density of the effective pion gap is required. Results are compared with previously obtained ones for the HDD EoS for which Mmax = 2.06 M . The cooling of the compact star in the supernova remnant Cassiopeia A (Cas A) is explained mainly by an efficient medium modified Urca process. To explain a > ∼ 2.5% decline of the cooling curve for Cas A, as motivated by an analysis of the ACIS-S instrument data, together with other cooling data exploiting the DD2 EoS a large proton gap at densities n < ∼ 2n0 is required vanishing for n > ∼ 2.5 n0, where n0 is the saturation nuclear density. A smaller decline, as it follows from an analysis of the HRC-S instrument data, is explained with many choices of parameters. With the DD2vex EoS and using an effective pion gap steeper decreasing with the density and/or a proton gap shifted to smaller densities we are also able to reproduce both a strong decline compatible with ACIS-S data and HRC-S instrument data. The mass of Cas A is estimated as 1.6 − 1.9 M , above the value 1.5 M , which we have evaluated with the softer HDD equation of state. Different mass choices for the hottest object XMMU J173203.3-344518 are discussed. We make general remarks also on hybrid star cooling and on its dependence on the stiffness of the hadronic EoS.PACS. 97.60.Jd Neutron stars -95.30.Cq Elementary particle processes -26.60-c Nuclear matter aspects of neutron stars

show abstract

Section: Hybrid Starsmentioning

confidence: 99%

Influence of the stiffness of the equation of state and in-medium effects on the cooling of compact stars

2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…Because the 2SC pairing pattern breaks the SU(3) color symmetry, one of the quark colors (say, the blue color) is not involved in that pairing. The strength and the flavor content of pairing among blue quarks is model dependent (Alford et al 2003;Schmitt et al 2003;Schmitt 2005;Aguilera et al 2005Aguilera et al , 2006Aguilera 2007). It is likely that cross-flavor (blue-up and bluedown) pairing is suppressed by a large mismatch between the Fermi surfaces of the up and down quarks.…”

Section: Modeling Cooling Processesmentioning

confidence: 99%

Rapid cooling of Cassiopeia A as a phase transition in dense QCD

Sedrakian

2013

A&A

View full text Add to dashboard Cite

We present a model of the compact star in Cassiopea A that accounts for its unusually fast cooling behavior. This feature is interpreted as an enhancement in the neutrino emission triggered by a transition from a fully gapped, two-flavor, color-superconducting phase to a crystalline phase or an alternative gapless, color-superconducting phase. By fine-tuning a single parameter -the temperature of this transition -a specific cooling scenario can be selected that fits the Cas A data. Such a scenario requires a massive M ∼ 2 M star and is, therefore, distinctive from models invoking canonical 1.4 M mass star with nucleonic pairing alone.

show abstract

“…[26,27,28], where also the special role of the spin-1 color-spin locking phase has been pointed out that here all quarks participate in the pairing with a gap of the order of 1 MeV or even below. This feature of the CSL phase is robust, as was demonstrated for our above isotropic ansatz for the spin-1 diquark current introduced in [29], and for its generalizations to the nonlocal case [30] and to a selfconsistent Dyson-Schwinger approach [31].…”

Section: Phase Transition To Quark Matter: Nucleon Dissociationmentioning

confidence: 72%

Single-flavor CSL phase in compact stars

Blaschke¹,

Sandin²,

Klähn³

et al. 2008

AIP Conference Proceedings

View full text Add to dashboard Cite

Abstract. We suggest a scenario where the three hght quark flavors are sequentially deconfined under increasing pressure in cold asymmetric nuclear matter as, e.g.^ in neutron stars. The basis for our analysis is a chiral quark matter model of Nambu-Jona-Lasinio (NJL) type with diquark pairing in the spin-1 single flavor (CSL), spin-0 two flavor (2SC) and three flavor (CFL) channels. We find that nucleon dissociation sets in at about the saturation density, no, when the down-quark Fermi sea is populated (d-quark dripline) due to the flavor asymmetry induced by ^^-equilibrium and charge neutrality. At about 3no u-quarks appear and a two-flavor color superconducting (2SC) phase is formed. The s-quark Fermi sea is populated only at still higher baryon density, when the quark chemical potential is of the order of the dynamically generated strange quark mass. We construct two different hybrid equations of state (EoS) using the Dirac-Brueckner Hartree-Fock (DBHF) approach and the EoS by Shen et al. in the nuclear matter sector. The corresponding hybrid star sequences have maximum masses of, respectively, 2.1 and 2.0 M©. Two-and three-flavor quark-matter phases exist only in gravitationally unstable hybrid star solutions in the DBHF case, whfle the Shen-based EoS produce stable conflgurations with a 2SC phase component in the core of massive stars. Nucleon dissociation due to d-quark drip at the crust-core boundary fulfllls basic criteria for a deep crustal heating process which is required to explain superbusts as well as cooling of X-ray transients.

show abstract

Nonlocality effects on color spin locking condensates

Cited by 35 publications

References 28 publications

Influence of the stiffness of the equation of state and in-medium effects on the cooling of compact stars

Influence of the stiffness of the equation of state and in-medium effects on the cooling of compact stars

Rapid cooling of Cassiopeia A as a phase transition in dense QCD

Single-flavor CSL phase in compact stars

Contact Info

Product

Resources

About